From: Paul Mackerras Date: Mon, 12 Dec 2011 12:37:21 +0000 (+0000) Subject: KVM: Add barriers to allow mmu_notifier_retry to be used locklessly X-Git-Tag: v3.4-rc1~59^2~71 X-Git-Url: http://git.openpandora.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=a355aa54f1d25dff83c0feef8863d83a76988fdb;p=pandora-kernel.git KVM: Add barriers to allow mmu_notifier_retry to be used locklessly This adds an smp_wmb in kvm_mmu_notifier_invalidate_range_end() and an smp_rmb in mmu_notifier_retry() so that mmu_notifier_retry() will give the correct answer when called without kvm->mmu_lock being held. PowerPC Book3S HV KVM wants to use a bitlock per guest page rather than a single global spinlock in order to improve the scalability of updates to the guest MMU hashed page table, and so needs this. Signed-off-by: Paul Mackerras Acked-by: Avi Kivity Signed-off-by: Alexander Graf Signed-off-by: Avi Kivity --- Reading git-diff-tree failed